激活TLR2通过促进神经细胞死亡诱导假激酶表达诱导肺上皮细胞凋亡

目的探讨特异性激活Toll样受体2(TLR2)对于小鼠MLE-12肺上皮细胞发生细胞凋亡的影响及其潜在的分子机制。方法应用(0、1、3.3、10、33)ng/mL的TLR2特异性配基PAM3CYS4处理24 h或用33 ng/mL PAM3CYS4处理0、8、16、24、36、48 h,激活肺上皮细胞MLE-12的TLR2,使用Western blot法检测神经细胞死亡诱导假激酶(NIPK)和活性caspase-3的蛋白表达,用TUNEL凋亡检测试剂盒检测细胞凋亡的情况。结果与正常培养的MLE-12细胞相比,特异性激活TLR2可以促进NIPK和活性caspase-3的表达增加,细胞凋亡的阳性细胞数目增加;使用siRNA技术特异性抑制NIPK的表达后,显著抑制活性caspase-3表达,凋亡细胞数减少。结论特异性激活TLR2可增加NIPK的表达,促进肺上皮细胞发生凋亡。     

Toll样受体3在病毒感染及细胞凋亡中的生物学功能

Toll样受体3（TLR3）作?《舅碦NA识别受体在机体抗病毒天然免疫中发挥十分重要的作用。TLR3识别配体后通过含TIR结构域的转接蛋白（TRIF）途径活化转录因子NF-κB和干扰素调节因子3（IRF3）,诱导炎症细胞释放炎症因子并介导炎症反应,同时诱导I型干扰素的释放,介导抗病毒天然免疫。在一些病毒感染中TLR3通过诱导组织损伤介导病毒的扩散从而加重疾病的严重程度。部分肿瘤细胞也表达TLR3,活化的TLR3介导细胞凋亡、抑制细胞增殖,提示TLR3可能是肿瘤免疫治疗的新靶点。［关键词］ Toll样受体3;信号转导;病毒;肿瘤;细胞凋亡     

TLR3的激活抑制乳腺癌细胞MDA-MB-231的增殖

目的 Toll样受体(TLRs)在肿瘤的发生发展和肿瘤免疫中起到重要的作用,有报道称TLR3的激活能够促进某些肿瘤细胞的凋亡.本研究旨在探讨TLR3的特异性激动剂Poly(I:C)对恶性程度较强的乳腺癌细胞MDA-MB-231增殖与凋亡的影响,并初步探讨其发挥作用的机制.方法 反转录PCR检测Toll样受体各个亚型在mRNA水平上的表达;CCK-8细胞活力试剂盒检测不同浓度Poly(I:C)对MDA-MB-231细胞增殖的影响;流式细胞术用Annexin V-FITC/PI染色检测Poly(I:C)对MDA-MB-231细胞凋亡作用的影响;实时定量反转录PCR检测相关细胞因子的表达变化.结果 在mRNA水平上,MDA-MB-231细胞TLRs各亚型中TLR3表达最高;CCK-8检测结果显示Poly(I:C)刺激以后,MDA-MB-231细胞的增殖受到抑制,凋亡试剂盒检测显示Poly(I:C)刺激以后对细胞凋亡没有影响;实时定量PCR显示TNF-α、IFN-β和IFN-γ在Poly(I:C)刺激6h后大约有20倍的升高.结论 Poly(I:C)刺激MDA-MB-231细胞后,细胞增殖受到抑制,但其凋亡并不受影响;TNF-α、IFN-β和IFN-γ可能在抑制增殖的过程中发挥一定的作用.     

TLR4在铜绿假单胞菌上清液诱导RAW264.7巨噬细胞凋亡中的作用

目的研究Toll样受体4(TLR4)在铜绿假单胞菌(Pseudomonase aeruginosa,PA)上清液诱导小鼠单核巨噬细胞RAW264.7凋亡中的作用。方法 RAW264.7巨噬细胞分为control组(不做任何处理)、MOD组(体积分数为0.10、0.20、0.30的PA上清液处理)、control+TAK-242组(TLR4阻断剂处理)、MOD+TAK-242组(体积分数为0.10、0.20、0.30的PA上清液处理+TLR4阻断剂处理),采用Hoechst染色法观察细胞凋亡后细胞核形态学变化,MTT检测细胞增殖抑制率,流式细胞术检测细胞凋亡,Western blot检测TLR4蛋白的表达。结果与control组相比,MOD组呈现不同程度的细胞凋亡(P0.05),且随着PA上清液体积分数的逐渐增加,细胞凋亡率不同程度逐渐增加(P0.05);加入TLR4阻断剂后,细胞凋亡率比MOD组明显降低(P0.05)。同时随着PA上清液体积分数逐渐增加,TLR4蛋白的表达不同程度逐渐增加(P0.05);加入TLR4阻断剂后,TLR4蛋白的表达水平降低(P0.05)。结论 PA上清液可以诱导TLR4表达,同时促进巨噬细胞的凋亡。然而加入TLR4阻断剂能够明显抑制TLR4的表达和巨噬细胞凋亡,可见TLR4在PA上清液诱导RAW264.7巨噬细胞凋亡中具有促进作用。     

TLR4/NLRP3炎症复合体介导对比剂诱导的肾小管上皮细胞炎症和损伤

目的:探讨Toll样受体4(TLR4)/Nod样受体蛋白3(NLRP3)炎症复合体是否介导了对比剂(CM)引起的肾小管上皮细胞炎症和损伤。方法:本研究运用碘普罗胺作用于大鼠肾小管上皮细胞NRK-52E建立损伤模型。应用CCK-8法测定细胞存活率;Western blot测定TLR4、NLRP3、凋亡相关斑点样蛋白(ASC)、caspase-1和cleaved caspase-3的蛋白水平;ELISA法检测炎症因子白细胞介素1β(IL-1β)和IL-18的水平;Hoechst 33258核染色法检测凋亡率;JC-1染色法测定线粒体膜电位。用小干扰RNA沉默NLRP3表达。结果:CM可降低NRK-52E细胞的存活率并上调cleaved caspase-3的蛋白水平(P0.05);此外,CM可上调细胞TLR4/NLRP3炎症复合体的表达并促进炎症因子IL-1β和IL-18的分泌(P0.05)。沉默NLRP3可以对抗CM诱导的炎症因子分泌;TLR4抑制剂TAK-242及沉默NLRP3能减轻CM引起的细胞凋亡和线粒体功能损伤。结论:TLR4/NLRP3炎症复合体参与了CM致急性肾损伤的发病机制,并介导了CM诱导的肾小管上皮细胞损伤和炎症。     

TLR4通路对polyI:C诱导肝癌细胞凋亡的影响

目的:研究TLR4信号通路活化对polyI:C诱导人肝癌细胞系H7402凋亡的影响,并分析其可能的作用机制。方法:用TLR4激动剂LPS处理H7402细胞24 h后,转染polyI:C刺激24 h,然后利用流式细胞术检测细胞凋亡,荧光定量PCR检测凋亡基因及胞内RNA模式识别受体TLR3、MDA5、RIG-I和LGP2的表达,Western blot检测识别受体的蛋白表达水平。结果:LPS预处理,减弱了polyI:C诱导H7402细胞凋亡的作用。同时,促凋亡基因Noxa的表达水平降低。在此过程中polyI:C的胞内识别受体RIG-I、MDA5的基因和蛋白水平表达下调。结论:LPS可能通过降低H7402细胞内dsRNA识别受体的表达,抑制了polyI:C诱导H7402细胞凋亡的作用。     

Toll样受体8激动剂在树突状细胞抗肿瘤免疫治疗中的研究进展

树突状细胞(DC)作为功能最强大的专职抗原提呈细胞,在诱导机体产生抗原特异性细胞毒性T细胞(CTL)中发挥重要作用。因此,现在的研究聚焦于使用免疫刺激性配体以增强DC在肿瘤中的抗原提呈功能,促进Th1型细胞免疫。由于小分子Toll样受体8(TLR8)激动剂直接激活DC、增强DC抗原提呈功能和细胞免疫应答,特别是Th1细胞应答。因此,TLR8激动剂已经成为抗肿瘤免疫调节药物或免疫佐剂的研究热点。本文在总结TLR8激动剂的结构和免疫调节作用的基础上,重点阐明TLR8激动剂增强DC免疫原性的机制,以及TLR8激动剂用于制备新一代DC疫苗的研究进展,探讨TLR8激动剂作为免疫刺激性配体在肿瘤免疫治疗中的临床应用前景。     

肿瘤坏死因子相关凋亡诱导配体在多种疾病中的生物学作用

肿瘤坏死因子相关凋亡诱导配体（Apo2L/TRAIL）是肿瘤坏死因子家族的一员,可以诱导表达特异性死亡受体TRAIL-R1 （DR4）或TRAIL-R2 （DR5）的细胞凋亡.TRAIL可诱导多种肿瘤细胞凋亡,对正常细胞无杀伤性,因此将其作为抗肿瘤靶向治疗候选药物之一,备受关注.近期研究发现,TRAIL既通过其受体介导细胞凋亡信号通路,又可传导非凋亡的信号通路,在自身免疫病和感染性疾病中发挥重要生物学作用.因而简单阐明TRAIL在人类多种疾病中生物学作用的研究进展,对今后TRAIL研究方向和治疗策略的选择具有指导意义.     

肽聚糖通过TLR2诱导人绒毛外滋养细胞的凋亡及意义

目的初步研究肽聚糖通过Toll样受体2(TLR2)诱导人早孕绒毛外滋养细胞株TEV-1细胞的凋亡及其意义。方法免疫细胞化学检测TLR2蛋白在TEV-1细胞的定位表达,不同浓度肽聚糖刺激TEV-1细胞后AnnexinV/PI流式细胞术检测细胞的凋亡率。结果①TEV-1细胞表达TLR2,且定位于细胞膜和细胞浆。②30μg/ml肽聚糖刺激TEV-1细胞24小时后与对照组比较,细胞凋亡率无明显增加(8.17±0.1%,P>0.05),而刺激时间延长至48h可诱导出明显增加的细胞凋亡(16.03±1.51%,P<0.01);大剂量组80μg/ml肽聚糖刺激TEV-1细胞24h、48h均可诱导明显增加的细胞凋亡(14.13±1.06%和51.67±1.56%,P<0.01)。结论人绒毛外滋养细胞株TEV-1表达TLR2,肽聚糖可通过TLR2诱导TEV-1细胞凋亡,且存在时间和剂量依赖性,提示宫内感染时G+菌可能通过TLR2介导胎盘滋养细胞凋亡来影响妊娠的结局。     

TLR7基因沉默通过NF-κB炎症通路对缺氧缺糖再给氧诱导的大鼠海马神经细胞凋亡的影响

目的 探讨Toll样受体7(Toll-like receptor 7,TLR7)基因对缺氧缺糖再给氧诱导的大鼠海马神经细胞凋亡的影响及机制.方法 根据TLR7mRNA编码序列设计并合成干扰siRNA序列,转染入大鼠海马神经细胞中,实验分为4组:对照组(Control)、缺氧缺糖再给氧模型组(Model)、TLR7基因沉...     

Properties of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) films modified with polyvinylpyrrolidone and behavior of MC3T3-E1 osteoblasts cultured on the blended films

A series of composite films of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) modified with polyvinylpyrrolidone (PVP) was prepared by varying the ratio of constituents, and their properties and cytocompatibility were evaluated. The hydrophilicity of the blended materials surfaces increased and the amounts of fibronectin and laminin adsorbed on the materials surface increased remarkably compared with PHBHHx. FT-IR spectra of the blended films showed a new band, implying that a surface physical interpenetrating network structure had formed. Scanning electron microscopy showed that there were dense pits and holes on the blended films surface. For the films of PHBHHx with 20 wt% and 40 wt% PVP, MTT assay indicated that PVP enhanced cell adhesion and proliferation, but that the effects were impaired by excessive PVP. The results suggested that proper addition of PVP increased the cytocompatibility of PHBHHx because the material surface had increased hydrophilicity and presented an appropriate morphology.     

Degradation of P(3HB) and P(3HB-co-3HV) in biological media

The biodegradability of oriented fibers made of polyhydroxybutyrate (P(3HB)) and its co-polymer with β-hydroxyvalerate (P(3HB-co-3HV)) was investigated in buffer solutions and in biological media in vitro and in vivo. The fibers of both polymer types demonstrated resistance to hydrolytic degradation in buffer solutions at 38°C and pH from 4.5 to 7.0 (for up to 180 days). It has been found that the biodegradation of the fibers in vitro in blood and serum and in vivo is accompanied by weight losses and minor changes in the microstructure with no significant losses in the tensile strength over a long time (up to 180 days). The biodegradation rate of the less crystalline co-polymer P(3HB-co-3HV) fibers was 1.4–2.0-times higher than that of the homopolymer P(3HB). It has also been shown that the degradation of the fibers in vivo is influenced both by tissue fluid enzymes and cells (macrophages and foreign-body giant cells). The fibers were eroded on the surface only with no gross defects and no dramatic effects on their mechanical performance.     

The Influence of Different Cultivating Conditions on Polymorphonuclear Leukocyte Apoptotic Process In Vitro,II: Ultrastructural Characteristics of PMN Populations Incubated with Proteinase 3 Anti-neutrophil Autoantibodies

The present study shows the effects of proteinase 3 anti-neutrophil cytoplasmic autoantibodies (PR3 ANCA) on polymorphonuclear leukocytes (PMN) apoptotic processes in vitro. The results are part of a generalized morphological analysis of 3 identical experiments on the influence of different cultivating conditions on the apoptotic processes. As controls, the authors use the results on spontaneous PMN apoptosis (Guejes L, Zurgil N, Deutsch M, Gilburd B, Shoenfeld Y. Ultrastruct Pathol. 2003;27:23–32) and PMN populations incubated with normal human IgG. Interaction of PR3 ANCA with the target antigen proteinase 3 (PR3) is one of the crucial pathogenic factors in Wegener granulomatosis (systemic autoimmune vasculitis). Following 40 min and 12 h incubation, PMN populations were evaluated by light microscopy, transmission electron microscopy, and immunogold electron microscopy. Twelve-hour cultures, either control or incubated with PR3 ANCA, contained different cell forms ranging from normal cells to cells at the final stages of apoptosis. Neutrophils at the state of complete manifestation of apoptotic phenotype were analyzed and compared. Three morphologically distinct apoptotic cell lines were characteristic for all PMN populations studied, regardless of cultivating conditions. As in spontaneous apoptosis, these cell lines are code-named “first,” “second,” and “third.” The present study has shown, firstly, that in the presence of PR3 ANCA, all 3 apoptotic lines were modified or altered. Secondly, the modifications or alterations of apoptotic cell lines effected by PR3 ANCA are specific for each cell line: the “first” line is characterized by intensification and modification of activation; the “second” by vacuolized cell forms; and the “third” by pronounced lytic alterations of the nuclei, while the cytoplasm is fully identical to that of control cell lines.     

The influence of different cultivating conditions on polymorphonuclear leukocyte apoptotic process in vitro, II: ultrastructural characteristics of PMN populations incubated with proteinase 3 anti-neutrophil autoantibodies

The present study shows the effects of proteinase 3 anti-neutrophil cytoplasmic autoantibodies (PR3 ANCA) on polymorphonuclear leukocytes (PMN) apoptotic processes in vitro. The results are part of a generalized morphological analysis of 3 identical experiments on the influence of different cultivating conditions on the apoptotic processes. As controls, the authors use the results on spontaneous PMN apoptosis (Guejes L, Zurgil N, Deutsch M, Gilburd B, Shoenfeld Y. Ultrastruct Pathol. 2003;27:23-32) and PMN populations incubated with normal human IgG. Interaction of PR3 ANCA with the target antigen proteinase 3 (PR3) is one of the crucial pathogenic factors in Wegener granulomatosis (systemic autoimmune vasculitis). Following 40 min and 12 h incubation, PMN populations were evaluated by light microscopy, transmission electron microscopy, and immunogold electron microscopy. Twelve-hour cultures, either control or incubated with PR3 ANCA, contained different cell forms ranging from normal cells to cells at the final stages of apoptosis. Neutrophils at the state of complete manifestation of apoptotic phenotype were analyzed and compared. Three morphologically distinct apoptotic cell lines were characteristic for all PMN populations studied, regardless of cultivating conditions. As in spontaneous apoptosis, these cell lines are code-named “first,” “second,” and “third.” The present study has shown, firstly, that in the presence of PR3 ANCA, all 3 apoptotic lines were modified or altered. Secondly, the modifications or alterations of apoptotic cell lines effected by PR3 ANCA are specific for each cell line: the “first” line is characterized by intensification and modification of activation; the “second” by vacuolized cell forms; and the “third” by pronounced lytic alterations of the nuclei, while the cytoplasm is fully identical to that of control cell lines.     

TNF配体相关分子-1A的研究进展

肿瘤坏死因子配体相关分子-1A(TL1A)是最近发现的一个新型细胞因子,属于肿瘤坏死因子超家族成员15。TL1A不仅具有诱导细胞凋亡、抑制肿瘤生长的作用,而且还具有活化T细胞、增加IFN-γ分泌等生理活性,在免疫调节及炎症性疾病中发挥重要作用。     

Insensitivity of PI3K/Akt/GSK3 signaling in peripheral blood mononuclear cells of age-related macular degeneration patients

Our recent studies with cultured retinal pigment epithelium cells suggested that overexpression of interleukin 17 receptor C (IL-17RC), a phenomenon observed in peripheral blood and chorioretinal tissues with age-related macular degeneration (AMD), was associated with altered activation of phosphatidylinositide 3-kinase (PI3K), Akt, and glycogen synthase kinase 3 (GSK3). We wondered whether or not altered PI3K, Akt, and GSK3 activities could be detected in peripheral blood mononuclear cells (PBMC) obtained from AMD patients. In the patients' PBMC, absentor reduced serine-phosphorylation of GSK3α or GSK3β was observed, which was accompanied with increased phosphorylation of GSK3 substrates (e.g. CCAAT enhancer binding protein α, insulin receptor substrate 1, and TAU), indicative of enhanced GSK3 activation. In addition, decreased protein mass of PI3K85α and tyrosinephosphorylation of PI3K50α was present in PBMC of the AMD patients, suggesting impaired PI3K activation. Moreover, abnormally lowered molecular weight forms of Akt and GSK3 were detected in PBMC of the AMD patients. These data demonstrate that despite the presence of high levels of IL-17RC, Wnt-3a and vascular endothelial growth factor, the PI3K/Akt/GSK3 signaling pathway is insensitive to these stimuli in PBMC of the AMD patients. Thus, measurement of PI3K/Akt/GSK3 expression and activity in PBMC may serve as a surrogate biomarker for AMD.     

柯萨奇病毒B3通过caspase依赖途径诱导HeLa细胞凋亡

目的 评价柯萨奇病毒B3（CVB3）致HeLa细胞死亡的方式及分子机制。方法 用CVB3作用于HeLa细胞,在不同时间收集细胞,通过相差显微镜、电子显微镜、流式细胞仪以及分子生物学手段,HeLa细胞的病变及caspase-3基因mRNA和蛋白质的表达。结果 CVB3作用于HeLa细胞后,细胞很快发生变性和坏死,24h后较多细胞凋亡;caspase基因在病毒作用早期即被活化,表现在caspase-3 mRNA在病毒作用后6h内,迅速增高达峰值。在24h内,又降至接近病毒作用前的水平。caspase-3蛋白表达在42h内逐渐增高。结论CVB3可诱导HeLa细胞发生坏死和凋亡两种反应,坏死早于凋亡,细胞凋亡与caspase-3的表达密切相关。     

Deletion of chromosome 3 and a 3;20 reciprocal translocation demonstrated by chromosome painting

The combined use of high resolution banding and chromosome painting techniques allowed us to identify a reciprocal translocation involving chromosomes 3 and 20 and simultaneous interstitial deletion of chromosome 3 in a patient with several minor anomalies of the face and hands. His karyotype is described as 46,XY,t(3;20) (p14.2;p12.2),del(3)(p11-p14.1). © 1995 Wiley-Liss, Inc.     

聚羟基烷酸酯、聚丁二酸丁二酯及其共混材料的细胞相容性评价比较

取家兔的骨髓间充质干细胞(MSCs)分别种植到聚羟基烷酸酯(PHBV)、聚丁二酸丁二酯(PBS)、及其二者共混材料(PHBV/PBS)上,每组材料又分为有孔和实心两种构型。用MTT实验、乳酸脱氢酶(LDH)实验、甲苯胺蓝染色和电镜等方法,观察MSCs在材料上的生长情况。比较三种材料六种构型分别对MSCs黏附和增殖的影响。结果以共混物实心材料的毒性最低,细胞增殖率最高。甲苯胺蓝染色结果显示兔MSCs在共混实心材料上的生长最佳,扫描电镜结果显示兔MSCs与共混实心材料黏附良好。共混物实心材料很有希望成为制备组织工程血管新型的支架材料。